A Personal Solar Power Plant

On the trail for several days? Keep your digital devices topped up with a simple but powerful solar panel and portable battery.

We like to travel with as little gear as possible, but today's digital devices continue to butt in where analog ones once sufficed. That goes doubly when we need to keep on top of work while on the road or on the trail: A mobile GPS unit is a must, an iPad or Kindle helps with stargazing and reading, a smartphone for taking pictures and keeping in touch, and maybe even a laptop if we're going away for a while. Keeping all that powered up when away from the grid is an ongoing challenge (hell, keeping them powered up long enough to last a day can be tough). One solution we're loving, and an alternative to the usual mobile battery route, is Goal Zero's Sherpa 50 and a Nomad13 solar panel.

The rugged Sherpa 50 from Goal Zero has quite a bit in the bells and whistles department. The unit has three ports: USB, 12V, and laptop, as well as an optional port to connect an AC inverter for powering standard 110 voltage devices (sold separately). And while the Sherpa has a relatively lightweight 50 watt-hour capacity, the addition of the Nomad 13 solar array means the battery can be recharged on the go, and then preserved for when you need it – a deciding factor for us. We also appreciate that it's light, at just over a pound, making it practical to attach the solar panel to the outside of a backpack and charge the Sherpa while out and about. That's pretty green any way you look at it.

Fully charging the Sherpa takes just three hours via an AC outlet, and a reasonable 6 to 12 hours using just sunlight on the 10.5- by 7-inch Nomad 13 array (less time if you opt for multiple solar arrays and daisy chain them together). The face of the device, where all the outputs and inputs are, has a battery level readout and the frame of each port lights up blue, green, or orange depending on output. A nice touch: There's a convenient and brilliant LED light that is handy in a pitch black tent in the middle of the night.

In direct sunlight, the Sherpa 50 happily sucked down the 13 watts from the Nomad solar panels and, after a day's hike, was ready to power a camp light, recharge our iPhone, and power our laptop – in fact, we still had enough power to write this very piece. We don't relish the need to pack extra gear, especially the tangled web of associated cables (the one real downside for these), but whether they're a modern convenience or necessity, our digital devices might as well be charged up in this particularly convenient and green way. [$220 for Sherpa 50, $160 for Nomad 13; goalzero.com]